Lifting-jack



C. W. FISHER.

LIFTING JACK. APPLICATION FILED Dc.1a.f\s|s.

Patented June 3, 1919.v

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LIFTING JACK. APPLWATIQN4 FILED bic. 16; |915.

Patented, June a, 1919.

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CHARLES W. FISHER, OFSPRINGFIELD, OHIO.

LIETnve-JACK.

Specification of Letters Patent. Patented June 3, 1919,

Application led December 16, 1915. Sera1No.67,256.

, An object of my invention is to provide means whereby the action of the pawl and Alat-chet mechanism may be readily reversed in a simple and effective manner.

A further and more specific objectv of the invention is to provide means for reversing the pawl and ratchet action which means is located in convenient reach of the operator upon the operating lever of the ack.

A further object of the invention is to provide means for readily releasing the jack bar to permit the same to be brought back to its lowermost position for storing purposes after the load is removed.

A further Vobject of my invention is to provide for indicating the limit of raising movement of the jack bar in order to prevent straining of the parts. A

A further objectV of the invention is to simplify and make more effective the operation of devices of this character.

In the accompanying drawings Figure 1 is a side elevation of a jack embodying my improvements, the side of the housing inclosing some of the operating parts being removed; the parts beingshown in raising position with the lever at the lower end of its stroke. y

Fig. 2 is a rear elevation of a portion of the main standard and ack Ybar showing the indicating device. 'l

Fig'is a section on the line 3 3 of Fig. 2 showing the indicating device in one position.

Fig. 4 is a similar section showing the indicating device in indicating position.

Fig. 5 is a longitudinal sectional view of the forward section of the operating handle or lever. f

Fig. 6 is atop plan view of the same.

. Fig. 7 is a longitudinal sectional view of the rear section of the operating handle or lever.V

Fig. 8 is an end view of the same.

Fig. 9 is aview of the forward side of the mechanism with the housings and standard broken away.

Fig. 10 is a side view of some of the parts shown in tFig. 1 the parts being shown in raising position with the operating lever at the upperl end of its stroke.

Fig. 11 is also a side .view of the same parts shown in lowering position, the operating lever being shown at the upper end ofy its stroke.

Fig. 12`is a view of the same parts also shown in lowering position with the operating lever at the lower end of its stroke.

Fig. 13 is a side elevation of the releasing device for the pawl showing the parts in normal position.

Fig. 14 is a similar viewv of the releasing devicesnshowing the same in operated position.

Referring to the drawings, 1 represents a standard having a base portion 2 and housings 3 and 4, this standard and the housings forming the inclosure and support for the various operating parts. A jack bar 5, having a lifting head 6 at its upper end, is slidably mounted in the standard and is arranged to be raised or lowered by a train of gearing operated by pawl and ratchet mechanism; the gearing consisting of a pinion 7 fixed on ak shaft 8 and meshing with the rack 9 on the forward yside o f the jack bar, a gear 10 also 'fixed on said shaft 8 and a pinion 11 meshing with said gear 10 and fixed to a shaft 12, said shaft 12 being operated by the pawl and ratchet mechanism now to be described. The shaft 12 is located in a bearing on the forward side of the standard 1 and extends from the housing 4, within which the pinion 11 is located, to a point within the housing 3 :where it is provided with a ratchet wheel 13 fixed' rigidly thereto. An operating lever formed in two parts, has its inner or-socket member 14 pivoted on said shaft 12 between vthe inner wall of the housing and the ratchet wheel, the outer or handle member 15 of said lever being removably connected thereto by the pivoted spring pressed catch 17 which engages the projec! tion 18. Pivotally connected to the lever member 14'is an operating pawl 19, a fiat plate 20 to which is connected a spring 21 bears against said pawl to normally hold the nose 19a thereof in engagement with the teeth of the ratchet wheel. This plate 20 lies loosely in the lower portion of the housing and has an upwardly extending projection 20L to which the spring is attached and which extends through a slot ina guilde20li Pivoted on a stud which extendsY laterally into the housing 3 is a holding pawl 23, this holding pawl being provided with a flat upper surface 239-' Arranged about the .stud between the holding pawl and the inner wall of the housing isa plate 24, said plate 24 having an enlarged open-,ing 25 which encircles the stud so.- that kthe plate is floating in character. The spring 2 1 pneviously referred to as, connected with the pla-te 20y is also connected with the plate 24,. The upper portion of the pla-te- 24 has. a laterally projecting flange 26 which liesl on the fiat surface- 2,3"L of the holding pawl. A plate. 27 lies on the projecting flange 26, it beingy yield-ablyheldin contact therewith by a spring 23 interposed between the,y plate 2'( and the upperpart of the housing a pin 29,v the upper end of which is.- secured to the housing and the lower end of which projects through openings in the plate and flange, serves to prevent. laterali displace ment of the parts, the ope-mpgs; being-- of suiiicient size. to; pre-vent binding of: the parts. E

Slidably mounted in the member 14 ofy the lever is a plunger- 30, they forward end of which has a lateralr projection, 3'1 which projects laterally through arecess 14.- and:l eX.- tends in proximity to, thev lowerportion of the plate 24E, thespringl serving to hold said plate yieldablyl aga-inst: said; laterali pro.- jection. Located' in the lever member 15 is a rod 32A having one end connected to a pi=v oted trigger in the nature! of a bell; crank lever, one arm 33Y of whichI is connected to the rod 32 and the other armi 34 of which extends through a slot inf the leverV member: The forward end; of the rodl isl slidably mountedI in; a guide 35 and interposed between this guideand av pin 3601-1 the rod is a spring 37 which serves tofnormalily hold the rodl in retracted position. 'Ehe forward endy of the rod; is-in linewith they near end of the pin 30v when. the lever member is-V asf. sembled, so that when the. trigger 34 is pulled rearwardly and the rodi 32A projected? forwardly it will cause the pin 30- to.- rock the plate 24 against the tension.- ofthe springs 21 and 29. This. rockin of: the plate will also rock the holding: paavl4 23' by: reason ofthe Contact of the i'ange- 26A with. the upper surface of said' pawlf, for thepur-v pose to be explained. When the trigger is thrown forwardly soasto retractthe rod? 32, the plate 24 will bel rocked in the opposite directionl by the spring 21 which in. turn throws the pin- 30 until' the lateral projec tion 31 thereonA contacts, with the rear wall ofthe lateral recess 142 in the member 14 which thus acts as a: stop against the further rocking of theV plate 24. By reason of the spring 21 it will be seen, however, that .vhatever the position of the parts, the projection 31 will he always in Contact with the rocking plate 24 so that when the lever l 1'5 is moved upwardly the plate 24 will be gia-*en a rocking motion by the contact of the projection therewith by reason of the faCt that the projection will move about the arc of a circle relative to the edge of the plate.

The operation as th-ns far described is as fol-lows Assuming that it is desired toraise the jack bar 5 with a load thereon, the trigger 34 is. pulled to. the rear which; projects the rod 32 and pinz 3Q: foifwardly, causing the lateral project-ion 31 to roch the plate 24 against the tensionv of the springs, thi-s rocking; of the pla-t6: alSO- swingingt-he holding pawluntil its nose eng-ages. with the teeth of the rachet wheel 13.y The parts are so adjusted.v that the- 'lange 2 6 of the plate- 24 will assu-me. a slight angular position relativelytothe upper surface of the pawl 23, as shown in Fig;Y 1, so, that the pressure of the spring-2S will be brought uponj the rear of; the paaivlfY sov as to; ho-ldsaid pawl in engagement withthe rachet wheel; So soon asthe leveris drawn upwardly, the lateral projection 31y contacting with the plate 24, will giive a further tilt to. saidf plate so to cause the flange 26 toassume the position sllowni in Eig;l 1.0 which also til-ts the plate- 2,7, and brings. a downward-ly and rea-rwardly extending portion', 2T' thereof in the. path of the ferwardside of a tail 19" on the operatingpawll 19, which not only serves to positivelyv hold the nose of the holding pawl 23 in engagement with the teeth of theratchet wheel, but will also assist thespring drawn plate 20 in forcing the nose of the operating paiwl' 19V back into engagement with the teeth of theratchet wheel as it ratchets over saith teeth. By manipulating the opera-ting lever up and down the required number of times, the jack bar is raised to the desired. position through the medium of the gearing heretofore described.

To lowerthe jzaclr bar, the trigger 34 is now/'thrown forwardlyV as a result of which the rod 32 is retracted permitting the spring 21 to rock they plate 24' until? the lateral projection 31 contacts-with the rear Wall' of the recess 14a. Assuming that the operatingl leverl has been left at the lower end of its stroke, this. brings the parts in the position shown1 in liiig. 12, in which -it will be seen that the nose ofthe holding pawlv 23 has been brought out of engagement with the teeth of theY ratchet wheel and is bei-ng held out by rea-son of the angular position assumedy by the flange 26 ofthe rocking plate 24, the weight of the load being held by the pawl 19. If the operating lever is now moved upwardly, the lateral projection 31, contacting asbefore with the rocking plate 24, tilts said plate until the nose ofthe holding pawl 23 is again brought into the path of the teeth of the ratchet wheel. In this position of the parts, however, the inclined portion 27 tof the plate 27 lies in the path 'of the rear portion ofthe tail 19b so that so soon as the tail of the pawl strikes this projecting portion it will throw the operating pawl 19 out of engagement with the teeth of the ratchet wheel as shown in Fig. 11, by reason of the pressure of the spring 28 upon the plate 27 which is suflicienttoovercome the pressure of the spring 21 upon the plate 20. In this positionthe plate 27 also assists in holding the pawl 23 in engagement with the ratchet-wheel with greater'force, as it will bek seen that an increased tension is placed upon the spring 28 and as the flange 26 bears on the rear end ofthe holding pawl the tension of the spring will be transmitted to that point of the pawl. In this position of the parts the rear wall of the slot 25 is hanging on the stud 22 by reason of the downward pressure of the springs 21 and 28 and also the pressure of the lateral projection 31 on the plate 24. rIn all other positions of this plate 24, however, it is of a floating character as the walls of the slot make no contact with the stud.

In order that theuppermost position of the jack bar may be indicated so that there will be no danger of an undue strain being brought upon the parts, I have provided the upper end of the standard 1 with a recess 40 in which is pivoted an indicator nger 41 the upper end of which is normally spring-pressed outwardly by a spring 42, in* terposed between the finger and jack bar 5. The jack bar 5 is provided with a recess 43, which when the jack bar has reached the limit of its upward movement, registers with the lower end of the indicator finger so that the spring 42 may throw the upperA end thereof out of recess in the standard, which thus indicates the position of the bar. When the bar is lowered the indicator finger will be automatically thrown back to the normal position in the recess. cator permits the position of the jack bar to be readily determined in places where the light is not sufficient for visual observation.

After the load 'has been removed from the jack bar, I have provided means for readily returning the bar back to its lowermost po'- sition without the necessity of ratcheting it back. The operating pawl 19 is provided with a laterally extending pin 44 and the holding pawl with a similar pin 45. Pivoted to the cover plate 3a of the housing 3 is a cam lever 46 the lower end of which projects through a slot 3b in the lower part of the housing within convenient reach of the operator. This cam lever is normally This form of indiheld by a spring 47 in the position shown in Fig. 13, in which position it is out of the path of the pins 44 and 45. When it is desired to lower the bar the lever is thrown to the position shown in Fig. 14 in-which position the cam surfaces thereon will Yhave contacted the pins and thrown both of the pawls out of engagement with the ratchet wheel, after which the bar may be readily pushed down to its -lowermost position.

I-Iaving thus described my invention, I 'claimz- 1. In a lifting jack, amain operating lever, a liftingV bar, `a ratchet wheel, an operating connection between said ratchet wheel land said ica-r, an operating pawl on said lever to cooperate with'ksaid ratchet wheel, a holding pawl to coperate with said ratchet wheel, and a single manually operated deviceon said lever for controlling said pawls in both the raising and lowering'operation of the same. A

2. 'In alifting jack, a main operating lever, a lifting bar, "a ratchet- 'wheel operatively connected with said bar, a. pivoted operating p awl on said lever, a pivoted holding pawl, 'spring operated means for holding said pawlsin engagement with the teeth of said ratchet wheel, and a single manually operated controlling device carried by said lever to control the action of said spring operated means in both the raising and lowering -operation Yof the devices.

3. In a lifting jack, amain -operating lever, a lifting bar, a ratchet wheel having an operative connection with said bar, a spring pressed operating pawl on said lever, a pivf oted holding pawl, yieldable devices associated with saidpawls and partly carried by ,saidllever for yieldablyv holding said pawls in engagement with the teeth of said ratchet wheel upon a raising movement of said bar, means carried by said lever for causing said devices to move said holding pawl out of engagement with the teeth of said ratchet wheel upon the lowering movement of said bar, and means operated by said lever for alternately throwing said pawls into 'and out of engagement with the teeth of said ratchet wheel upon the lowering movement of said bar.

4. In a lifting jack, amain operating lever, a lifting bar, a ratchet wheel having an operative connection with said bar, a spring pressed operating pawl on said lever, a pivoted holding pawl having a flat upper surface, a spring pressed plate associated with said holding pawl having a flange arrangedV along said flat surface, and means carried by said i operating lever for rocking said plate so as to maintain said holding pawl yieldably in engagement with the teeth of said ratchet wheel during the raising movement of said bar and to alternately throw it into and out of engagement with said ratchet wheel duringthe-lowering movement of said bar.

5.l InaA lifting jaek,=ama;in operating lever, ali-ttiing bar, a ratehet wheel having an op.i erative connection with said loa-r, a spring pressed operating pawl on said lever, apivotved holding ptt-wl, a spring pressed pla-te associated with said holding pawl, together withv controlling means on. said; lever for causing said' plate to maintain said' holding pawl yieldahly in engagement with said ratchet wheel during the upward movement of said bar and tocause it toI alternately engage `and disengage said ratchet wheel during the downward movement of said bar, and means operated by said plate for releas,` ingl said operating pawlf from said ratehet wheel during the down-wardmovement of said bar. Y

6. In a lifting jack, a main operatingle-ver, a lifting loar,l a ratchet. wheel having an operative connection with said bar, an operating pawl on said lever,V a holding pawl, a single manually operated device operable from said lever for Changing the relation of said holding pawl relatively to; said ratchet wheel inelnding means foryieldably hold.- ing said holding lpaw/l in engagement with the teeth of said ratchet wheel; during the raising movement of said, bar and for alternately throwing said operating and holding pawl into. and out off engagement. with said ratchet wheel during thelowering movement of said har.

7. In. a lifting jaolga, main operatinglever, a lifting har, a ratchet wheel having an op,- erative connection with said bar, an opere ating pawl connected with said lever,A aholding pawl, tail piece on said. operating pawl, a yieldable member associated with said holding pawls, said member being arranged to; Contact one side. of said tai-l piece during the lijf-ting movement. of the bar and the other side of said tail pieee duringthe lowering increment oi' said loa-r.

8. In lifting jaelgainairoperatinglever Consisting oat an outer and inner member, a lifting hant a ratchet wheel having an opera-- tive eonneetion' with said har; an operating pawl on said leversA a pivoted holdingfpaw-l, a spring p-l'ate-A associ-ated with said holding pawl',l afslidalele pia carried hy the inner mein-loer of said; lever with whichl said plate is in yielding Contact, 'a spring pressed rod earriedhy Said onter-lever-memher arranged in line with said pin, means. for projecting and retracting said rod to canse i-.t to change the-'position o-t said platev through themedi-'LL-m of' said pin so; as to. ehange theV relation of said hold-ing pawl relatively to said raltehet wheel.l

9'. In a lifting jack, a lifting han, a main operating lever,A an operating pawl on said lever having operative connection to said ban a holding pawh for said bar, means for holding said pawls in operative relation with said barrand means independent of said lever for throwing said pawls out of operative relation with said bar to permit said bar to; he pushed tov` lowermost position.

In testimony whereof., I have heremito; set my hand this 13th day of Deoemloer, 1915.

CHARLES WV. FISHER.

Witness:

CHAs; I., WELCH,

Copies of this patent mayl 'neY obtained for five cents each,vl by address/ing the CQmmissional 0f Ieltellts.k

Washington, D. ft 

